U.S. patent application number 11/093348 was filed with the patent office on 2005-11-10 for double coil occluder.
This patent application is currently assigned to NMT Medical, Inc.. Invention is credited to Chanduszko, Andrzej J., Widomski, David R..
Application Number | 20050251154 11/093348 |
Document ID | / |
Family ID | 35240385 |
Filed Date | 2005-11-10 |
United States Patent
Application |
20050251154 |
Kind Code |
A1 |
Chanduszko, Andrzej J. ; et
al. |
November 10, 2005 |
Double coil occluder
Abstract
An occluder that has a coil on one or both sides of a medical
defect, particularly a septal defect such as a patent foramen ovale
(PFO). Each coil can be formed as a tube that is hollow, with or
without a closed end. The tube can be delivered over a wire. For
occluding a PFO, the coils can be designed to provide a compressive
force to one or both of septum primum and septum secundum.
Inventors: |
Chanduszko, Andrzej J.;
(Chandler, AZ) ; Widomski, David R.; (Wakefield,
MA) |
Correspondence
Address: |
WILMER CUTLER PICKERING HALE AND DORR LLP
60 STATE STREET
BOSTON
MA
02109
US
|
Assignee: |
NMT Medical, Inc.
Boston
MA
02210
|
Family ID: |
35240385 |
Appl. No.: |
11/093348 |
Filed: |
March 30, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60568526 |
May 6, 2004 |
|
|
|
Current U.S.
Class: |
606/151 |
Current CPC
Class: |
A61B 2017/00575
20130101; A61B 2017/00623 20130101; A61B 2017/00867 20130101; A61B
2017/00606 20130101; A61B 2017/00619 20130101; A61B 17/0057
20130101; A61B 2017/00592 20130101 |
Class at
Publication: |
606/151 |
International
Class: |
A61B 017/08 |
Claims
What is claimed:
1. A device adapted to press together the septum primum and the
septum secundum between the atrial chambers, the device comprising:
first and second clamping spirals, each having a size suitable for
use on each side of the septum and a central connector for
connecting the first and second clamping spirals and passing
through the tunnel between the septum primum and the septum
secundum, wherein the spirals include hollow tubes along their
length.
2. The device of claim 1, wherein the spirals spiral outwardly from
the central connector to free ends.
3. The device of claim 1, wherein the central connector includes at
least one hollow rod extending from a central region of the first
spiral to a central region of the second spiral.
4. The device of claim 1, wherein the spirals and the central
connector are formed from a single monolithic tube.
5. The device of claim 1, wherein at least one of the spirals has a
radially extending portion extending from the central connector and
the spirals extend inwardly back to the central connector.
6. The device of claim 1, wherein the device is formed from a
bioresorbable polymer.
7. The device of claim 1, wherein the spirals each circle around
more than 360.degree..
8. The device of claim 1, wherein the central connector includes a
scaffold for promoting tissue growth.
9. The device of claim 1, wherein at least one of the first and
second spirals has a first end rigidly connected to the central
connector and a second end with a connector adapted to be connected
to the central connector so that each end of the spiral is
connected to the central connector.
10. The device of claim 9, wherein a first end of each of the first
and second spirals includes a radial portion connected to the
central connector and a second end is at the central connector.
11. The device of claim 10, wherein the central connector has an
opening at at least one end, and the second end of one of the
spirals is adapted to extend through the opening to form a
connection.
12. The device of claim 10, wherein the central connector and the
second end have a snap-fit connection.
13. The device of claim 1, wherein the first spiral spirals
outwardly from the central connector and extends from an outermost
point radially back to the central connector where the radial
portion is connected to the central connector.
14. The device of claim 13, wherein the radial portion is
detachably connected to the central connector.
15. The device of claim 13, wherein the radial portion is
non-detachably connected to the central connector.
16. A device adapted to be disposed in a patent foramen ovale
tunnel and comprising first and second spaced apart spirals and a
connecting member together connected to the spirals with respective
first and second joints, wherein each spiral has one end connected
to one of the first and second joints, and a second end connectible
to the respective first or second joint, the spirals forming closed
loops when the second end is connected.
17. The device of claim 16, wherein the spirals spiral outwardly
from the first and second joints and have a radial portion
extending inwardly from an outermost part of a spiral.
18. The device of claim 16, wherein the connecting member includes
two wires extending between the first and second joints.
19. The device of claim 16, further comprising a membrane attached
to the connecting member for promoting tissue growth.
20. The device of claim 16, wherein the first and second joints
have an opening for the second end to extend through.
21. The device of claim 16, wherein the first and second joints
have snap fit connectors for connection to the respective second
ends.
22. A method comprising introducing into a patent foramen ovale
(PFO) the device of claim 1.
23. The method of claim 22, wherein the introducing includes first
providing a wire into the body, and then providing the device over
the wire.
24. The method of claim 23, wherein the method includes loading the
device into a sheath, providing a catheter to limit movement of the
device in the proximal direction, and providing the catheter,
device, and sheath to the region near the PFO.
25. The method of claim 24, further comprising extending the sheath
and device through a PFO tunnel to a left atrium, limiting movement
of the device in the proximal direction, and withdrawing the sheath
in the proximal direction to release the second spiral on the left
atrium side of the PFO.
26. The method of claim 25, further comprising further withdrawing
the sheath in the proximal direction.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from provisional Ser. No.
60/568,526, filed May 6, 2004, which is incorporated herein by
reference.
BACKGROUND
[0002] This invention relates to an occluder for closing a septal
defect.
[0003] A PFO, illustrated in FIG. 1, is a persistent, one-way,
usually flap-like opening in the wall between the right atrium 10
and left atrium 12 of the heart. Because left atrial pressure is
normally higher than right atrial pressure, the flap formed by
septum primum 14 and septum secundum 16 usually stays closed. Under
certain conditions, however, right atrial pressure can exceed left
atrial pressure, which creates the possibility that blood could
pass from the right atrium to the left atrium through a PFO tunnel
18 and allow blood clots to enter the systemic circulation. It is
desirable to avoid this situation.
SUMMARY
[0004] Embodiments of the present invention relate to an occluder
that has a coil on one or both sides of a medical defect,
particularly a septal defect such as a patent foramen ovale (PFO).
Each coil is preferably provided as a tube that is hollow, with or
without a closed end. In some embodiments, the tube can be
delivered over a wire.
[0005] In the case of use for occluding a PFO, the coils can be
designed to provide a compressive force to one or both of septum
primum and septum secundum of a PFO. The device can further include
a tissue scaffold.
[0006] Other features and advantages will become apparent from the
following detailed description and drawings.
DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a cross-sectional view showing a patent foramen
ovale (PFO).
[0008] FIGS. 2A, 2B, 3A, 3B, and 4 are various side, end, and
perspective views of a device according to a first embodiment of
the present invention.
[0009] FIGS. 5-8 are partial side and partial cross-sectional views
showing delivery of the device of the type shown in FIG. 4.
[0010] FIGS. 9 and 10 are perspective views of additional
embodiments of a device according to the present invention.
[0011] FIGS. 11-16 are perspective, plan, end, and side views of an
occluder according to another embodiment of the present
invention.
[0012] FIGS. 17 and 18 are perspective views of another embodiment
of the present invention, which is a variation of the embodiment of
FIG. 11.
[0013] FIGS. 19 and 20, and FIGS. 21 and 22 are perspective views
of two additional embodiments of the present invention.
[0014] FIGS. 23-26 are partial cross-sectional, partial side views
of a device of the type shown in FIG. 22 being delivered to a
PFO.
[0015] FIG. 27 is a perspective view of another embodiment of the
present invention showing coils with outer ends rigidly connected
to a center joint.
[0016] FIG. 28 is a perspective view showing the device of FIG. 27
in a partially stretched form for loading into a catheter.
[0017] FIGS. 29-32 are partial side, partial cross-sectional views
showing the delivery of the device of the type shown in FIGS. 27
and 28.
DETAILED DESCRIPTION
[0018] The present invention relates to embodiments of a septal
occluder with one or two spiral coils, including a double spiral
coil embodiment. The coils are preferably hollow with open or
closed ends, and either or both are designed to provide a
compressive force when deployed in a septal defect, such as a PFO.
While the coils are preferably formed from hollow tubes that can
increase the strength of the spirals over solid wires, solid wires
could be used. The hollow tubes may also be easier to deliver, and
can be provided over a wire. Another double spiral coil design is
shown in provisional application Ser. No. 60/528,022, filed Dec. 9,
2003, and in the nonprovisional Ser. No. 11/008,539, filed Dec. 9,
2004, each of which is expressly incorporated by reference.
[0019] Referring to FIGS. 2A-4, in this embodiment, an occluder 20
has two coils, a proximal (right atrial) coil 22 and a distal (left
atrial) coil 24. These coils are coupled together through a center
joint 26. This center joint has a first collar 28 at an inner end
of coil 22, a second collar 30 at an inner end of coil 24, and
connecting rods 32 and 34 coupling collars 28 and 30. As indicated
in FIGS. 2B and 3A, rods 32 and 34 are preferably in a horizontal
plane in a position shown in FIG. 4 in a manufactured and
non-deployed position.
[0020] Referring to FIG. 3B, when occluder 20 is in the deployed
position in a PFO, coils 22 and 24 each have an upper portion in
contact with septum secundum 16 and a lower portion in contact with
septum primum 14. As is also indicated, rods 32 and 34 and center
joint 26 can extend side-by-side in, and conform to, the geometry
of the PFO tunnel between septum primum 14 and septum secundum
16.
[0021] The coils can be made from a number of different materials,
including metal or nonmetal. Among nonmetals, a preferable material
is a polymer, which can be a bioresorbable polymer. In this
embodiment, the ends of the coils are shown as being open, but one
or both of the ends could be closed, either with a solid piece or
with a mesh. In this embodiment, the coils spiral outwardly from a
central location.
[0022] As shown in FIG. 5, the device with coils in the form of
hollow tubes can be mounted over a wire 36 that extends through an
inner catheter 38. Wire 36 and catheter 38 are both in a delivery
sheath 40. The device with coil 24, coil 22, and center joint 26 is
in a substantially elongated and a low profile configuration, such
that they fit into a sheath that is preferably 10 French or
smaller, although a larger sheath could be used.
[0023] As shown in FIG. 5, sheath 40 is inserted into the left
atrium. Referring to FIG. 6, sheath 40 and wire 36 are retracted,
while inner catheter 38 is maintained in its current position to
hold the position of coil 24. These relative movements, which can
be at the same or at different rates, allow coil 24 to be released
from delivery sheath 40 and into the left atrium. The coil is
preferably formed from a material with good shape memory properties
so that it returns to its coil form when released from sheath 40.
Such a material is especially useful when the coil has a free outer
end not connected to anything else.
[0024] Referring to FIGS. 7 and 8, sheath 40 and wire 36 are
retracted further while inner catheter 38 is used to help maintain
conduit 22 in a desired position. With such further removal, the
center joint is positioned within the PFO tunnel, and coil 22 is
allowed to resume its coil shape on the right atrial side of the
PFO.
[0025] The device is formed with suitable materials, dimensions,
and configuration so that the coils provide enough compressive
force to hold together septum primum and septum secundum
sufficiently to prevent clots from passing from the right atrial
side to the left atrial side. As will be apparent below, while
occluder 20 has a spiral that is connected to a center joint and
spirals outwardly (i.e., with an increasing radius) to a free end,
in other embodiments, the coil spirals inwardly from the center
joint and may have an end that is connected to the center joint. In
this embodiment and others, the outer surface can be roughened to
produce an inflammatory effect to encourage healing. In this
embodiment and others, a single coil can be used on one side of the
defect, with another structure, such as an umbrella-shaped
structure on the other side of the defect.
[0026] FIG. 9 is a perspective view of another embodiment of the
present invention in which a device 90 is formed from a single,
monolithic hollow tube shaped to form a distal coil 94, a proximal
coil 92, and a connecting segment 96 that extends from the inner
ends of coils 92 and 94. If desired, portions of device 90, such as
at connecting segment 96, can have whiskers that can be formed by
gluing short threads of the material used to make the tube or some
other material, or connecting segment 96 can be partially shaved or
otherwise frayed. The use of whiskers can serve as an inflammatory
agent that encourages healing. While mentioned here, whiskers could
be used in other embodiments.
[0027] Like the embodiment of FIG. 1, the inner ends (i.e., smaller
radius portion) of the coils are coupled to a connector or
transition to a connecting segment, and the outer ends of the coils
are free and are not connected to any other structure.
[0028] Referring to FIG. 10, in another embodiment of the present
invention, a device 100 has a proximal coil 102 and distal coil
104. In this case, one of the coils, in this case coil 102, starts
spiraling from the inside where there is a free end, and spirals
out with increasing radius to an outer end of coil 102 where the
coil is then curved away from the plane of the spiral and is
connected to a collar 108 of a center joint 106. Distal coil 104 is
shaped in a similar manner.
[0029] As is further indicated in FIG. 10, a tissue scaffold 109
can be incorporated into center joint 106. The scaffold is
connected between the collars and can be bounded by the connecting
rods between the collars, although it could be used at other
locations instead of this location or additionally at other
locations. While shown between the connecting rods, it can extend
around the connecting rods and/or around other portions of the
device to encapsulate them. The tissue scaffold promotes
encapsulation and endothelialization, thereby further encouraging
anatomical closure of septum primum and septum secundum. While
shown just in FIG. 10, a tissue scaffold can be incorporated into
other embodiments.
[0030] A tissue scaffold can be formed of any flexible,
biocompatible material capable of promoting tissue growth,
including but not limited to polyester fabrics, Teflon-based
materials, such as ePTFE, polyurethanes, metallic materials,
polyvinyl alcohol (PVA), extracellular matrix (ECM) or other
bioengineered materials, synthetic bioresorbable polymeric
scaffolds, other natural materials (e.g. collagen), or combinations
of these materials. A tissue scaffold or the spiral or center joint
can have drugs or biological agents to improve the defect healing
process and/or to prevent clotting.
[0031] Referring to FIGS. 11-16, a device 110 according to still
another embodiment can have close-ended hollow or solid spirals,
and can have a free end of a coil on one or both sides of a defect
locked to a center joint (FIG. 11) or unlocked (FIG. 12). By
locking one or both free ends of a spiral to a center joint, the
clamping force of the device can be increased relative to a device
with a free end.
[0032] A center joint 116 has a latching loop 120 connected to an
outer end of coil 114. From the inner end of coil 114, there is a
free end 128 that can extend a short distance through loop 120.
Similarly, coil 112 has an outer end attached to a latching loop
118 and an inner end that extends to a free end 130 that extends a
short distance through the opening in loop 118. Free ends 128 and
130 each have a bent end that extends through latching loops 118
and 120 in a manner that they stay in the latched position.
Latching loops 118 and 120 are connected together with connecting
rods 122 and 124.
[0033] Additional views of this device are shown in FIGS. 13-15 and
in FIG. 16 which shows the device as deployed. FIG. 15, in
particular, shows how the latching loops 118 and 120 are coupled to
the outer ends of the spiral, the spirals extend inwardly, and at
the inner end of the spiral, a free end 128, 130 extends to the
latching loop on each side. As is also shown in FIG. 16, the
connecting rods 122 and 124 (not shown) have some ability to bend
and conform to the geometry of the PFO tunnel, while the spirals
can provide a compressive force between septum primum and septum
secundum.
[0034] FIGS. 17 and 18 show an embodiment of a device 170 that is
similar to that in FIGS. 11 and 12, except that rather than having
free ends extending a short way through loops and held in the loops
with bent ends, it has locks, such as magnetic locks, 172, 174 on
the free ends. In this case, the free end has one magnetic piece
and the center joint has another magnet and a conforming mechanical
structure, such as a short lug and an opening for receiving the
lug.
[0035] Referring to FIGS. 19 and 20, a device 190 has features of
several of the embodiments above. The device has a proximal coil
192 and a distal coil 194 connected together through a center joint
196 that includes collars 198 and 199. Coil 192 is rigidly
connected to a side of collar 198 from where it extends radially
outwardly and then spirals inwardly until at an inner part of the
spiral, it bends toward the center. At the center, there is a bent
end that can extend through collar 198 to hold it in place. In this
case, the interior end of the loop has a bent end for engaging the
collar, but it could have the reverse form with the inner end of
the spiral connected to the collar and the outer end of the spiral
curved to extend through the collar. Coil 194 in this embodiment is
similarly connected to the other side of the device, although the
different coils can have different structures.
[0036] FIG. 20 shows device 190 of FIG. 19 with the inner ends of
the coils detached from the respective collars.
[0037] FIGS. 21 and 22 show embodiments similar to those in FIGS.
19 and 20, except that the connection between the spiral and the
center joint has a snap fit to hold them together. The device is
shown with the center joint and spiral detached in FIG. 22. In this
case, like the embodiment of FIGS. 19 and 20, the coil spirals
inwardly from the outside to a lock, but it could have the reverse
form of spiral.
[0038] FIGS. 23-26 show the delivery of a device of the type shown
in FIGS. 21 and 22. FIG. 23 shows the device of FIG. 21 loaded into
a sheath 230, and coupled to a mandrel 240 and a delivery catheter
242. As shown herein, the device has a small profile, preferably
small enough to fit in a 10 F sheath. Referring to FIG. 24, sheath
230 with the loaded device is provided through the PFO tunnel and
into the left atrial side. Sheath 230 is then retracted while an
end cap 234 of distal coil 232 is held in place by mandrel 240 to
allow a distal coil 232 and end cap 234 to be released from sheath
230. A proximal end cap is held in place with delivery catheter
242.
[0039] Referring to FIGS. 25 and 26, end cap 234 coupled to collar
235, e.g., with a snap fit, and mandrel 240 (not shown here) is
withdrawn. Sheath 230 is then further retracted to release a
proximal coil 236 against septum primum 14 and septum secundum 16
on the right atrial side until end cap 244 is coupled to collar
246. Delivery catheter 242 is releasably detached from end cap 244,
resulting in the positioned device as shown in FIG. 26. The
releasable connection between catheter 242 and end cap 244 can be
with grappling hooks 250 (FIG. 25), which are generally known for
use in delivering medical devices.
[0040] FIGS. 27 and 28 show another embodiment of the present
invention similar to that shown in FIGS. 21 and 22, except that the
device is shown with a center joint that has a rigid and generally
non-separable connection to both coils. FIG. 28 shows the device of
FIG. 27 in an elongated form as it would be loaded into a sheath
for delivery. With further elongation, the profile of the device
can be reduced to fit inside a delivery sheath as shown in FIG.
29.
[0041] FIGS. 30-32 show the release of the device of FIGS. 27 and
28 in the PFO tunnel. This delivery is generally similar to that
described in conjunction with FIGS. 23-26. A device 270 with a
distal coil 272, proximal coil 274, and center joint 276 is
elongated as shown in FIG. 28 and loaded into a delivery sheath
278. A first delivery catheter 280 is releasably connected to a
portion of coil 274 at a proximal end, and a second delivery
catheter 282 is releasably connected to a portion of distal coil
272 with a connection 284. As shown in FIG. 30, sheath 278 is
withdrawn while second delivery catheter 282 holds distal coil 272
in place so it can open into a coil on the left atrial side. As
shown in FIGS. 31 and 32, sheath 278 is further retracted to allow
right atrial coil 274 to open on the right atrial side. Coil 274 as
shown is releasably held with hooks 290 to provide control over the
release. Having described embodiments of the present invention, it
should be understood that modifications can be made without
departing from the scope of the invention.
* * * * *